Anh, Nguyen Dong, Ninh Quang Hai, and Werner Schiehlen. “Extended Averaged Equation Method and Application on Analyzing Some Nonlinear Deterministic Vibrations”. <i>Vietnam Journal of Mechanics</i> 31, no. 1 (March 18, 2009): 1–16. Accessed November 9, 2025. https://vjmech.vast.vn/vjmech/article/view/5490.